FP794COMPARISON OF BODY COMPOSITION THROUGH BIOIMPEDANCE ANALYSIS BETWEEN YOUNG AND ELDERLY HEMODIALYSIS PATIENTS: HYDRATION AND NUTRITIONAL STATUS

Abstract

Introduction and Aims: The number of old people on dialysis is rising rapidly. Overhydration and malnutrition are a severe problem in elderly dialysis patients. However, there are very few studies on the nutritional and hydration status in this group. We aimed to compare the hydration and nutritional status between young and elderly hemodialysis (HD) patients and to analyze risk factors related to overhydration and malnutrition in these patients. Methods: We conducted a cross-sectional study, in which 112 HD (male 56, mean age 59.0+/-12.5 years) patients were enrolled. We collected various data; anthropometric data such as body mass index (BMI), triceps skinfold (TSF), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), handgrip strength (HGS); laboratory data such as total protein, albumin, total iron-binding capacity (TIBC), hemoglobin, total cholesterol, blood urea nitrogen (BUN), creatinine ; bioimpedance analysis (BIA) data such as intracellular water (ICW), extracellular water (ECW), total body water (TBW), ECW/TBW ratio, protein, mineral, skeletal muscle mass (SMM), bone mineral content (BMC), body cell mass (BCM), fat free mass (FFM), TBW/FFM ratio, phase angle (PhA); and traditional nutritional assessment method for dialysis patients like malnutrition-inflammation score (MIS). All patients were stratified as young (< 65 years, n=77) and elderly (> 65 years, n=35) patients. Results: TIBC, triglyceride and HGS were significantly lower in elderly patients than in young patients. Also, ICW, protein, mineral, SMM, BCM, BMC, PhA by measured BIA were significantly lower and ECW/TBW and TBW/FFM were higher than in young patients. Age was negatively correlated with HGS (r = -0.443, p = 0.000), PhA (r = -0.481, p = 0.000), and BCM (r = -0.330, p = 0.003) and positively correlated with ECW/TBW (r = 0.503, p = 0.000). In multivariate regression analysis, age, the presence of diabetes and PhA was independent risk factor of ECW/TBW representative of hydration status in HD patients (s = 0.111, p = 0.031; s = 0.102, p = 0.035; s = -0.865, p = 0.000). Age and PhA were independently associated with MIS representative of nutritional status in HD patients (s = -0.258, p = 0.024; s = -0.569, p = 0.000, respectively). Conclusions: ICW was lower and ECW/TBW was higher in elderly patients, as compared to young patients, although there was no difference in TBW by BIA between elderly patients and young HD patients, which implied that elderly patients have an overhydration status, as compared to young patients. Also, we found that PhA were a significant independent factor of overhydration and malnutrition in HD patients. Therefore, our results indicated that the measurements of BIA might be a clinically useful method for assessing nutritional and hydration status in HD patients.